Light microscopy is an essential tool for many sciences. In recent years, the use of electronic image recording using both high light and low light level cameras has revolutionized the use of the light microscope. These tools, combined with the availability of a multitude of fluorescent indicators and photoactivatable reagents have made routine experiments that were impossible only a few years ago. During this time, however, illumination sources have not kept pace with the acquisition tools. We propose here to develop a multiwavelength flashed illumination system capable of providing: a bright, uniform field; controllable wavelength; gated intensity; controlled illumination energy; sufficient energy for releasing photosensitive reagents; and low electromagnetic interference. For combining imaging modalities, such as interference contrast and fluorescence, alternate frames or fields (or any combination) can be illuminated in the trans- or epi- modes without moving parts. The proposed device is a second generation prototype initially built at SUNY with development funds supplied by SUNYLAB. The device will incorporate changes suggested by work on the first prototype. PROPOSED COMMERCIAL APPLICATION: General purpose illuminator for multiwavelength switching, strobing, trans- or epi- inode illumination.